Yz250 350 big bore kit. Complete list of cylinder kits with parts and labor.

Yz250 350 big bore kit com The PRO-SERIES delivers unmatched throttle response, torque, and top-end power through a precision-machined billet bore design and advanced internal fuel circuitry. Mar 8, 2024 · Adding a big bore kit thus transforms the KTM 350 SX-F into an even more formidable contender. Find top brands, exclusive offers, and unbeatable prices on eBay. Simply bolt it up! Explore a wide range of our Ktm 250 Big Bore Kit selection. 00 mm. Heard great things about these kits. 95 Niche Standard Bore Standard Bore Top End Repair Kit for Yamaha Raptor Warrior Grizzly Wolverine 350 1987-2011 MK1001141 1 New Cylinder Works Big Bore Kit 468cc for 04-13 Yamaha YFZ 450 23001-K01 1 Shop Wiseco Motorcycle Big Bore & Top End Kits for Yamaha YZ250 with eBay Guaranteed Fit. 5 MM OR 76 MM The increase of bottom-end power the Athena big-bore produces is impressive. 00 USD 4 interest-free installments, or from $76. MAXLOCK head stud kit. A. Aug 16, 2023 · Cylinder Works 21009-K01 Big Bore Cylinder Kit Compatible With/Replacement For Yamaha YZ 250 1999-2023 STD Compression Ratio, 72 mm Cylinder Diameter, 295 cc Displacement, 5. Kit is for big bore size - 98. Athena’s Big Bore Cylinder Kits guarantees an increase in performance that can be observed along the power curve, keeping the reliability at the same level of the original components. Big bore power-valve. Are the basically worth the money? The big bore kits are cool, but I dont see myself putting a ton of money into an older yz. heavier) YZ450FX (240 LBS. 8:1, Cylinder Diameter: 80 mm, Cylinder Kit Type: Big Bore, Displacement: 270 cc, Engine Type: 4-Cycle, Includes Cylinder, Piston Kit, and Top-End Gasket Kit, Size Over Standard: 3mm Compatible With/Replacement For: Yamaha WR 250 F 2020, YZ 250 F 2019-2020, YZ 250 FX 2020 1-year warranty protects you after The kit includes the high-quality aluminum cylinder with increased bore, the cylinder head, the complete piston with the piston pin and rings, the exhaust valve kit, and all the necessary gaskets. – 262 LBS. I primarily ride MX, intermediate level. It is my understanding that the nothing needs to be modified to use Athena Banshee 66mm Kits Yamaha Banshee 350 Athena 370cc 66mm Big Bore Cylinders Gaskets WISECO Pistons Part #: (A-BAN66LRC / 513M06600 / A-BAN-BI B1005-A) Starting from $659. 60) today when you shop RevZilla for your Cylinder Works Big Bore Cylinder Kit Yamaha YZ250F / WR250F / YZ250FX 2014-2020! Free Shipping, Lowest Price Guaranteed & Top of the Line Expert Service. 51 plus free shipping at Parts Giant. 21009-K01 Big Bore Cylinder Kit Compatible With/Replacement For Yamaha YZ 250 1999-2023 STD Compression Ratio, 72 mm Cylinder Diameter, 295 cc Displacement, 5. Athena Head Stud Kit. com 98mm Big Bore Cylinder Jug 478cc Barrel Fit for Yamaha YFZ450 YFZ 450 2004-2013 Features: Cast Aluminum cylinder has super-high silicone content for additional strength. Includes- - Big bore Cylinder - Athena top end gasket kit with head & base gasket, muffler copper washer. ? Cylinder is nickel-carbide plated with enlarged water passages for exceptional durability and performance ? Bore increased to 72mm (stock is 66. Shop Motorcycle Big Bore & Top End Kits for 2000 Yamaha YZ250 with eBay Guaranteed Fit. Jan 30, 2007 · Buy BBR Motorsports 120cc Big Bore Kit with Cam 411-HXR-1001: Rebuild Kits - Amazon. Jul 9, 2025 · A 290cc big bore kit (check price on Amazon) will increase torque and horsepower by simply swapping your cylinder and piston assembly. 350$ Yz250 , two stroke , Yamaha , big bore kit , dirtbike , motorcycle . No engine modifications required. We service your cylinder by stripping the old plating, inspecting the cylinder and performing necessary repairs. Increase YZ250 1999-2019 300 Big Bore kit. THIS KIT COMES WITH THE CYLINDER, HEAD, PISTON, POWER VALVE ,AND GASKETS 75. Feb 7, 2023 · We consider a yz250 2 stroke big bore kit to be a worthy investment in the long run. Motorcycle and Scooter Cylinder kits Click here to learn more about thermal units and discover how they are installed. 60mm Size Over Standard Athena’s cylinder kits and its components are recognized worldwide for their performance, durability and reliability. Nov 21, 2016 · Does the 293cc kit for the yz250 cut fall off in the top and rid range i herd thats the problem with that kit is it true i like to pin my bike for a few secounds wot and i dont want to lose any top end power /fall off any one ever used this kit Apr 27, 2017 · First 2-Stroke Yamaha YZ ESR 325 with a Combined Optimized Efficiency (CEO) Big Bore Cylinder Kit to make the Monster Energy Cup Main Show (Finished 19th) and Hole Shot in the LCQ against Performance/Factory 450’s. Vertex Forged Moly Coated 72mm Big Bore Piston Kit (Includes, Piston, Pin, Rings & Clips) (Perfect For Pump Gas) Wiseco or Wossner Piston Kit Upgrade Available! YZ250 riders looking for more power, this big bore cylinder kit transforms your 250cc engine into a potent 295cc powerhouse! Specifically designed for Yamaha YZ250 models from 1999-2023, this complete kit includes everything you need for the conversion: cylinder, cylinder head, power valve kit, piston kit, top end gasket set, and wrist pin bearing. We offer the best customer service in the industry! Used (normal wear), Eddie sanders racing 325 big note kit for a yz250. Here is the big bore kit proposed by ATHENA to increase the capacity of your motocross / enduro YAMAHA YZ 250cc from 2003 to 2021. Explore a wide range of our Yz250 Big Bore Kit selection. com Shop Motorcycle Big Bore & Top End Kits for 2002 Yamaha YZ250 with eBay Guaranteed Fit. Order top end rebuilds kits online at Wiseco. Power made easy. Maintains a Stock Style in Appearance. Make an offer!; Athena Big Bore Complete Cylinder Kit (392cc) 68. Part Number 2002-2014 YZ125-250 Polisport Restyling Kit and DeCal Works Graphics Installation. The 265 has been ported for broadband use. And to make things easier for you, the kit also includes the correctly sized piston, rings, wristpin, and gaskets to fit your new larger displacement bore perfectly. Fits Yamaha YZ250 2 Stroke Dirt Bikes. M-Spec 2-Stroke Big Bore Kits are ported for your riding style and require modification to your power valve and cylinder Save 5% ($38. Nov 9, 2011 · Only one currently using the Athena YZ big bore 293cc kit. Ported power valves for more power and torque over the stock YZ250. Yamaha YZ295 BIG BORE KIT $850 . Shop now for fast shipping and easy returns! HONDA TRX250R PARTS BIG BORE KITSWE RACE WHAT WE SELL Eddie Sanders Racing has been developing products for nearly 25 years! That experience has given us the ability to bring you some of the most innovative and successful designs the industry has to offer: We pride ourselves in the vast array of services and products we supply to quad racers all over the world. May 6, 2020 · Buy Wrench Rabbit Complete Engine Rebuild Kit starting at $251. Cylinder Works cylinder head machined for 72mm big bore. Kustom Kraft Performance has been designing and building Big Bore kits for over 40 years. Pistons $119 & up We have Std. Nov 4, 2017 · By using an Athena kit AJ took one of the truly great bikes of the modern era in the YZ250 and made it into something the average trailrider would drool over and, if Yamaha is listening, put a headlight on it and we will buy them. They replace your stock Original Equipment Manufacturer (OEM) parts and increase horsepower and torque by increasing the engine size (displacement). The additional compression is no joke. Paid almost over 800 for this . | Browse our daily deals for even more savings! | Free shipping on many items! FITS ALL 1999 AND NEWER YAMAHA YZ250 TWO STROKE MODELS - READY TO BOLT ON AND GO! Full Polisport restyling kit for the 2002-2021 Yamaha YZ125 and YZ250 with Gas Tank and Seat. HAS GREAT POWER AND SMOOTH POWER . This is a bolt on kit, no case mods needed. , Oversize & Big Bore pistons available from ESR, LAPC, Pro-X & Wiseco. Every component is purpose-built for performance, including a fully integrated dual-jet system, and proprietary Xcelerator metering rod. Athena Head. RK Tek designs and builds custom 2 stroke aftermarket performance heads for ATV's ,snowmobiles, and motorcycles. Oct 12, 2014 · Picked up a 2000 Yz 250 last week, for a 2nd bike to build as a big bore. Anyone have personal experience with the big bore kits on newer yzf's? Aug 15, 2024 · Anyone have any experience with these kits and jetting? Mostly riding single track love the 250 but am interested in a 300. The added 20cc increases bottom-end torque and top-end horsepower, with a big hit from mid-throttle. com Athena Big Bore Piston and Cylinder Kit 290cc - Yamaha YZF250 WR250F Aluminum cylinder nickel-carbide treated Special design increasing cooling liquid volume Bronze dome head Forged piston, skirts coated with molybdenum disulfide treatment Delivered with piston, piston rings, circlips, axis and seals. Curious what peeps have to say about Athena kits. 293cc Big bore kit for 1999 to 2021 Yamaha YZ250. Original piston siezed so it will need a bore and hone and new piston which esr can provid you with . MAXLOCK cylinder stud kit. 00 mm) Cylinder for 1999-2024 Yamaha YZ250 Is your Yamaha YZ250 losing power due to a worn-out cylinder or broken power valve? This kit has a lot of porting done the cylinder has good bottom end great mid and top end works best with race fuel someone looking for maximum power 805-440-1063 Text to get a call back. RK Tek also builds one of a kind custom CNC machined parts for any application. Simply bolt it up! Keep all your original parts! YZ250 Big Bore 293cc Kit 1999-2024. Jan 17, 2022 · I rebuilt my YZ 250 engine with wiseco crank and a 293cc big bore kit. – 247 Wet or 16 LBS. Some big bore kits will also include other items like bigger carburetors, performance camshafts, and big valve cylinder heads to deliver additional M-Spec Service Big Bore Kits are based around your modified OEM cylinder. 134cc Big Bore kits for most 125's $600. Oct 11, 2022 · 󰍸 25 󰤦 29 󰤧 Poul Linneberg The Athena kit is over awesome kit it makes close to 10hp more it is very god kvality it is 15:1 though so con rod and gearbox life May be shortend but I really miss mine just cant afford to run it 3 yrs 2 Jamie Cloutier I got the Athena 293cc big bore with a hot rod crank off eBay and installed in the spring Feb 23, 2015 · I am about to order my new top end and piston for my 1999 YZ. Complete list of cylinder kits with parts and labor. 32 ,34, 36 or 38mm Mikuni carb, jetted to 4stk performance specs, comes as complete kit with carb,throttle,throttlecable and air filter for both the 250 and 350 XL, 72 to 78 Apr 19, 2024 · All Balls Racing Group is pleased to offer the new YZ250 Big Bore Cylinder Kit from Cylinder Works. 99 Nov 8, 2025 · YZ250 Big Bore 293cc Kit 1999-2022. 60 Out of stock Out of Stock Sale! 1997 Yamaha YZ125 134cc Big Bore Service Kit From: Millennium Technologies $ 758. This Kit increases displacement on your bike with top-quality parts all in one package. My questions for those run an Athena 300 kit are below: I was curious if any of you guys know about Yamaha YZ250 big bore kits? I did a bit of hunting, and found a few kits ranging from 270cc to 300cc's. 00 with my core exchange. Big Bore power for the stock cylinder and head. Many sizes In-Stock Dec 29, 2017 · Followers6 Message added by ThumperTalk Shop YZ250 Big Bore Kits Prev 1 2 Next Page 2 of 2 Buy Cylinder Works Big Bore Cylinder Kit starting at $393. This all-in-one bolt-on kit is designed for riders seeking significant performance gains without the hassle of extensive modifications. Removing casting flaws will gain significant power in The kit includes the high-quality aluminum cylinder with increased bore, the cylinder head, the complete piston with the piston pin and rings, the exhaust valve kit, and all the necessary gaskets. detailed descriptions and prices. A bigger bore increases the engine displacement, thus giving you a "bigger engine". Dry - 228 Wet) (YZ 325 - 214 LBS. The ports get the rough casting flaws removed and finished with a glass beaded finish. I had to lean out the main at least 3 steps from the original jet. Oct 23, 2024 · This big bore kit will include a cylinder, head, piston, gaskets, bearing, head-studs and alignment pins $1,295 Available Christmas 2024 The new kit for the CR500 will include an all-aluminum plated cylinder with a decompressor- head, piston kit and gaskets. Find the perfect Cylinder Works parts for your Yamaha, with 0% financing! Dec 13, 2010 · I had a 2007 CRF 250 With in Athena 280 big bore kit on it and to top it off my buddy worked at white brothers during the time they closed up shop and gave me one of the Tom Morgan race team spec heads from some Honda team ported with xelydine valve adjustable Cam timing etc etc it was badd ass when I made it that big bore kit with that spec head and a little boy carbon fiber white brothers Brand Big Bore Kit Sort By: Newest L. com Honda big bore kits and Honda ATV big bore kits. link/big-bore-kit-yz3 Ever wondered what it's like to ride a YZ250 with a 300cc big bore kit? We've got the answers! $39. With a 3mm Big Bore Cylinder Kit, you'll see noticeable increases in horsepower and torque, making this an excellent choice for weekend riders and vet racers looking for more power. Apr 24, 2014 · I believe ESR is the best VALUE Big Bore with the BROADEST power band available! Yamaha YZ with ESR 325 Kit - (250 was 212 LBS. 15 plus free shipping at Parts Giant. This kit fits Yamaha YZ250 d Order the Cylinder Works Big Bore Kit Yamaha YZ250F 2019 CW21013K01 for the 2019 Yamaha YZ250F at Vivid Racing. There are a lot of big-bore kits to choose from, but we elected to go with L. 60mm A big bore kit typically consists of a new larger bore cylinder, piston kit, and top end gaskets. Order the Cylinder Works Big Bore Kit Yamaha YZ250F 2019 CW21013K01 for the 2019 Yamaha YZ250F at Vivid Racing. - Athena Forged Piston Kit with piston, rings set, wrist pin & clips. Jan 21, 2017 · L. Done it on my 2001 Yz 250 and loved it !!!!!!!!!!! Question is-- Do i go 295 or the 325 ??? Who has ridden both size kits ??? What are your thoughts and which on Apr 17, 2014 · my past experience with a big bore kit on a carb yz290 it needed less fuel. Includes cylinder, cylinder head, piston kit w/rings, power valve and top end gasket. 95 Pack Size: ea Qty / Unit: 1 Add to Cart THIS KIT IS A SERVICE KIT. Wiseco Big Bore Kits Shop for Engine at Rocky Mountain ATV/MC. Developed For Professional Racing Applications. Suzuki Big Bore Kits How Would You Like 15% More Low End for Your Suzuki?Then we've got just what your looking for. 72/mo with Check your purchasing power May 31, 2022 · Wanted to put out my review of the Magnum big bore kit for the 2001 Yamaha YZ250 since there isn't much info on them. Big bore top end gaskets. Increase torque and power Feb 19, 2025 · Step-by-step guide on installing a big bore kit for the YZ 300X engine to enhance performance and power. Dry est. Dec 17, 2017 · BRC are expanding into the Yamaha YZ250 market with their big bore kits, so there is clearly a demand there. Give your YZ the 2022-2026 look Cylinder Works Big Bore Kit: https://rmatvmc. I also have a big bore scooter for my kids when they where younger and it required the same thing. Building a bike on a budget? PORTED AFTERMARKET CYLINDERS for 2005-21 YZ125,134,144 $350-$550 USPS PRIORITY MAIL INCLUDED! These aftermarket cylinders are designed by Eric Gorr for better reliability over original cylinders. The forged and coated piston kit includes 2 rings, pin, bearing, and circlips. 5MM . More torque and useable power for trail riding. The bikes have improved a great deal since th eold engine was in production. These kits include a ported and Nikasil plated cylinder, cylinder head, all 3 powervalves and center retaining clip (swapped from new 2024 yz250 cylinder), new Yamaha studs, and COMETIC MLS head gasket and top end gaskets, o-rings, and copper washers. SLEEVE presents the latest Two Stroke Big Bore Kit: the YZ300 Kit for the Yamaha YZ-250! This kit will cover years from 1999 thru 2017. 58 Out of stock Order the Athena 72mm Big Bore Cylinder Kit Yamaha YZ250 2T 2003-2021 P400485100042 for the 2003-2021 Yamaha YZ250 at Vivid Racing. . Size Over Standard5. Full kit includes new big bore cylinder, piston, power-valve, power-valve barrels, gasket set, and cylinder head. May 30, 2011 · ATHENA 300cc Big Bore Kit for YZ250 This all new two-stroke kit increases YZ250 displacement to 293cc. Nov 7, 2025 · YZ250 Big Bore 293cc Kit 1999-2022. Great deals. Not interested in the ESR kit, but open to other companies supplying a cylinder. ) Weight Benefit over YZ 250FX, (231 LBS Dry est. THE POWER IS VERY EASY TO CONTROL THE POWER VALVE OPENS A LITTLE LATER TO MAKE IT EASY TO RIDE ON A SLICK TRACKS . I also Oct 20, 2016 · Which one would you pick? The Twisted Development modified YZ250F and Twisted Development/ Cylinder Works YZ270F are a blast to ride. A couple test riders’ feet were injured trying to start ours with tennis shoes. 4mm); stroke remains the same as stock (72mm) ? 15:1 compression ratio ? Forged, domed piston ? No case machining necessary ? Kit includes cylinder Yamaha YZ250 engine rebuild kits, and YZ250 parts to suit every need, some with just the basics and others with every bell and whistle you can think of. Hotrods Heavy Duty Crank Shaft. 16 Out of stock Out of Stock Sale! 1998-2000 Yamaha YZ125 134cc Big Bore Service Kit From: Millennium Technologies $ 760. The Cylinder Works big bore kit is an affordable and effective solution for boosting horsepower and increasing engine displacement, all while maintaining the bike's OEM aesthetics. You already have your “KTM beater” in your stable waiting for this hop-up! So check out our YZ300 in the March 2017 issue of MXA Magazine to see how it’s done. Each product is thoroughly 134cc Big Bore kits for most 125's $600. 00mm Bore For Yamaha YFZ350 Banshee 19872006 P400485100024 684944 $1,11810 FREE delivery Apr 25 - 28 293cc Big Bore Kit - Yamaha 99-21 YZ250 (72mm). Special design consideration was given to the exhaust bridge area on the small bores and porting on the big bores. Boost the performance of your engine with a top end kit, which comes with forged pistons, a gasket kit, and all the components you need to get the job done. This kit fits Yamaha YZ250 d Sep 15, 2018 · The MXA wrecking crew wanted to build a big-bore Yamaha YZ250. I can do the 250 or the 265 for about the the same price. 5 330 KIT STANDARD IS 75. Millennium Technologies Standard Bore Service Kits were developed to provide you a complete top-end rebuild for your 2-stroke dirt bike. com Sale! 1995-1998 Yamaha YZ250 265cc Big Bore Service Kit From: Millennium Technologies $ 807. Shop now for fast shipping and easy returns! Innovative PerformanceAthena 300cc kit, 85mm Piston for 2019-2023 YZ250F and YZ250FX Models. We plate the cylinder bore with our Vertex Forged Moly Coated 72mm Big Bore Piston Kit (Includes, Piston, Pin, Rings & Clips) (Perfect For Pump Gas) Wiseco or Wossner Piston Kit Upgrade Available! Oct 23, 2024 · This kit has an interesting development that dates from 1992, while working for TUF Racing, the biggest Kawasaki KX dealer the USA, I experimented with big bore 250s converted to 300s. Sold the bike and I don’t have a need for it anymore . SLEEVE Big Bore Kit 270cc - LAS5536 Yamaha YZ-250F - 270cc 2005-10 Big Bore Cylinder Kits: Designed for enthusiasts aiming to improve performance, with an enlarged bore cylinder, corresponding piston, and necessary gaskets for assembly. SLEEVE has developed a big bore kit that utilizes your stock cylinder and head to 💥Cylinder Works Power Valve Kit - CW-PV-K01 - Big Bore (72. com Aug 18, 2002 · Hi Eric I'm a experienced machinist in SOUTH AFRICA and would like to know the specs[head,ports,crankshaft] for converting the 2001 YZ250 to a 300. You May 20, 2023 · The Big Bore kit for the 2019-2023 Yamaha YZ250F, the Cylinder works Big Bore 270cc kit could be just what you need. -Forged Piston, rings, clips, pin, top end bearing and top-end gasket kit. Sleeve’s YZ300 Grip & Rip big-bore kit. Magnum MX National Big Bore Kit YZ250 Compression Ratio: STD Cylinder Diameter: 72 mm Cylinder Kit Type: Big Bore Displacement: 295 cc Engine Type: 2-Cycle Includes: Cylinder, Cylinder Head, Power Valve Kit, Piston Kit, Top End Gasket Kit & Wrist Pin. com FREE DELIVERY possible on eligible purchases Jun 28, 2010 · Does anyone have any feed back on any big bore kits that they have installed on their Rappys Fueling,reliability,overheating? I would also like to know some good stories of how pleased you are with what ever kit you purchased (by name)or what you would do differently. The kit includes: Boring and replating your cylinder. Yamaha YZ295 BIG BORE KIT $850 $850. Longevity Oct 8, 2018 · L. Wet) – (30 LBS. Ce kit en Ø72mm contre Ø66mm d'origine permet ainsi de passé votre moto de 250cc a 294cc réel! M-Spec Service Big Bore Kits are based around your modified OEM cylinder. com Voici le kit big bore proposé par ATHENA pour augmenter la cylindré de votre motocross / enduro YAMAHA YZ 250cc de 2003 à 2021. ca. Shop Motorcycle Big Bore & Top End Kits for 1994 Yamaha YZ250 with eBay Guaranteed Fit. Wiseco Pro-lite piston, rings, pin and clips, top-end bearing and a top-end gasket set. and they should have. Seems like the 270 kits are fairly common, but not finding much on the 304 kits. Which company or what person does the best big bore kit ? Is Eric Gorr no more ? Buy Cylinder Works Big Bore Cylinder Kit 21009-K01 For Yamaha YZ 250 1999-2023 STD Compression Ratio at Walmart. Shop now for fast shipping and easy returns! Oct 17, 2025 · Made with larger water jackets for greater cooling capacity. Let’s take you step by step, type by type, and find the best yz250 2 stroke big bore kit for you. Shop Athena Motorcycle Big Bore & Top End Kits for Yamaha YZ250 with eBay Guaranteed Fit. M-Spec 2-Stroke Big Bore Kits are ported for your riding style and require modification to your power valve and cylinder Get the best deal for Motorcycle Big Bore & Top End Kits for Yamaha YZ250 from the largest online selection at eBay. 00 on your cylinder. I ended up just wanting a regular 250 piston in there and need to get rid of this cylinder. What Is A Big Bore Kit? A big bore kit comes with a larger-sized piston and a cylinder that is already machined to size. It’s our most responsive, most refined, and most race-ready carburetor. Browse for more products in the same category as this item: 2 STROKE MOTORCYCLE > MOTORCYCLE YAMAHA YZ250 1999-2019 BIG BORE 2 STROKE MOTORCYCLE > NEW NEW HONDA CR250 92/01 BIG BORE Brand Big Bore Cylinder Kit Sort By: Newest Cylinder Works Big Bore Cylinder Kit 270cc - 51004-K01 KTM 250 EXC-F 2014 Shop Motorcycle Big Bore & Top End Kits for Yamaha YZ250 with eBay Guaranteed Fit. This kit in Ø72mm against Ø66mm of origin thus makes it possible to pass your motor bike of 250cc has 294cc real! Jan 9, 2018 · The current YZ250 power curve/delivery is good so i'm not aiming to create a torque monster that doesn't rev, just looking to add more power throughout the current range. facility for a complete suite of modifications and then perfectly matched to a high-performance piston and gasket kit. cylinder Head and powervalve, Namura 72mm piston, rings, pin and clips, and top-end gasket set. Your cylinder or engine cases are shipped to our state of the art Plymouth, WI. Bottom Line on Athena YZ125 144cc Big Bore Kit: If you just want a quick overview of the Athena Big Bore Kit (Check price on Amazon), here's what you should know: Information YAMAHA YZ250 TO 270cc BIG BORE KIT. Aug 11, 2025 · FITS ALL 2003 AND NEWER YAMAHA YZ250 TWO STROKE DIRT BIKES. Kits include Piston, rings, clips and pin ( NO BEARING ) 310 KIT STANDARD IS 72MM 330 BOLT ON KIT STANDARD IS 75. Massive selection from top brands on eBay. BIG BORE KIT FEATURES:. Oct 8, 2018 · L. The kit includes: 72mm 293cc big bore cylinder. 99 Sep 8, 2025 · Has me thinking a new/newer YZ250fx with a big bore kit would be a possible next bike for me. I'm looking into one as its a cylinder supplied big bore kit. Athena Big Bore kits are the go-to option when chasing more power for your ride, These are great bolt on power upgrades. We recommend always wearing a boot when trying to kickstart an Athena YZ big-bore kit. Coming from the depths of eBay Jay Clark saved these two Eric Gorr Racing. 293cc. Has anyone tried Athena's "new" 304cc version? Does it require new fuel trimming on the app, can I keep the stock exhaust, and is there any differences in vibration? They seem to care a lot about reliability so I Apr 17, 2021 · Mike Alessi put his trust in the ultra-trick ESR YZ325 “CEO” big-bore kit to race at the 2020 World Two-Stroke Championship. Step by Step process on how to update your Yamaha YZ125 or 250. heavier) (Note: Fuel weighs 8 LBS 5 days ago · Athena 72mm Complete 300cc Big Bore Motor Rebuild Kit! 72mm 300cc Nikasil Athena Big Bore Cylinder. Fits a number of years . I was curious if any of you guys know about Yamaha YZ250 big bore kits? I did a bit of hunting, and found a few kits ranging from 270cc to 300cc's. Only for YFZ450 carburetor model, will NOT work with YFZ450R Fuel Injected Model. Our Suzuki Big Bore kits can produce up to 30% more displacement and… 12:1 Big Bore 366cc Cylinder Kit designed for Yamaha Warrior 350 (1987-2004) Includes piston rings, pin, and gasket kit for a complete rebuild Features a high compression ratio of 12:1 for improved performance Teflon-coated side and ceramic top piston for enhanced durability Upgraded metal gaskets included for better sealing and reliability Jul 9, 2025 · But, for some of us that just want a little more out of a small-bore two-stroke, an upgrade in displacement is probably on top of the modifications list for your YZ125. Take off the old parts and install a 293cc New cylinder, power valve, piston and gaskets. Browse for more products in the same category as this item: 2 STROKE MOTORCYCLE > MOTORCYCLE YAMAHA YZ250 1999-2019 BIG BORE PISTON KITS WILL WORK IN ESR CYLINDERS AND PRO X CYLINDERS Replacement Piston Kits 310,330,350, 420,430 MADE FOR ESR BY WISECO Replacement Piston Kits for our big bore cylinder kits. RK Tech Athena’s cylinder kits and its components are recognized worldwide for their performance, durability and reliability. Apr 1, 2008 · I've decided my 15 yz250 needs more power in the near future. Made with larger water jackets for greater cooling capacity. Top End Gasket Kit Pair it with our GET ECU for proper tuning and get maximum gains No case machining needed, direct bolt on. com Explore a wide range of our Big Bore Kit Yz250 selection. Not a lot out there on reviews for the big bore kits on newer yzf's. Sized to Description Cylinder Works Big Bore Cylinder Kits for KTM, Husaberg, Husqvarna 250/350 The Cylinder Works Big Bore Cylinder Kits have increased bore size and increased compression (most models) that add up to a double bang for the buck that delivers more low-end grunt and quicker acceleration. Jan 18, 2019 · Here's a complete list of what's included in the kit: - 1 cylinder head with 69mm valve (No camshaft) - 2 rocker arms for 69mm valves - 1 oil pump assy with driving gear - 1 50mm bore cylinder block - 1 set of 50mm piston assy, piston, rings and wrist pin - 1 full set of engine gasket - 1 set of intake manifold and muffler bolts - 1 set of 4 gram racing roller weights - 1 set of 5 gram racing Innovative PerformanceAthena 300cc kit, 85mm Piston for 2019-2023 YZ250F and YZ250FX Models. Unlock the true potential of your 2019-2025 Yamaha YZ250F with the DYNAMIC RACING 80mm 270cc Big Bore Kit. Gunna get the SSS suspension conversion, no doubt about that. 60mm Size Over Standard The dimensions of the big bore cylinder are sized to fit your stock engine without any machine work or modification. Yamaha Big Bore Kits for all Yamaha motorcycles and ATVs including all needed parts and labor. -Big Bore Moly 2000 Cylinder Sleeve. YOU MUST SEND IN YOUR CYLINDER AND CYLINDER HEAD AFTER PURCHASING THIS KIT. Simply bolt it up! The Cylinder Works Big Bore Cylinder Kit for Yamaha has increased bore size and compression that deliver more low-end grunt and quicker acceleration. Increase Part 21009-K01 Cylinder Works Big Bore Cylinder Kit Retail Price: Your Price $1,106. Find the perfect Athena parts for your Yamaha, with 0% financing! Shop Cylinder Works Motorcycle Big Bore & Top End Kits for Yamaha YZ250FX with eBay Guaranteed Fit. Purchase a top end rebuild kit today! Athena 300cc kit, 85mm Piston for 2019-2023 YZ250F and YZ250FX Models. $350. Bought a cylinder works big bore to 295cc for a yz250. Specifications Yamaha YZ250 03-22 Yamaha YZ250 YZ 250 72mm 300cc Athena Big Bore Cylinder Top End Piston Kit Part #: (A-P400485100) Starting from $1,249. Big Bore Kit Includes: High quality 85mm forged piston Wrist Pin and clips Specially designed, cast and plate cylinder to fit maximum size bore and maintain strength. Find the perfect Cylinder Works parts for your Yamaha, with 0% financing! Sep 15, 2018 · The MXA wrecking crew wanted to build a big-bore Yamaha YZ250. Aug 17, 2020 · Specs: Description: Big Bore Cylinder Kit, Uses Vertex #24405, Compression Ratio: 13. Shop Motorcycle Big Bore & Top End Kits for Yamaha YZ250F with eBay Guaranteed Fit. Cylinder head modified for the big bore piston. In addition to Engine, browse our full selection of Parts & Accessories. L. The 250 would be completely stock. Originally designed by Eric Gorr for Magnum distributing under the brand name MAGNUM MX-COMPONENTS. zvq voo tdbk ywz zwphgi kgahue dyxk qrmqc lxbw zzgmbt qqsbm dqwfsbm nxbis ijvpo pjn